7. Texas Instruments TI-99/4 (1979)

With the release of the TI-99/4 in 1979, integrated-circuit pioneer TI took its first shaky steps into the home computer market with a $1150 package that included a special monitor and a calculator-like Chiclet keyboard. Like the original Apple II, the 99/4 did not support lowercase letters. Because of this limitation, the Shift key served as a function modifier, with the functions typically marked on a plastic overlay. The most frustrating of these key combinations was Shift-Q, which would quit a program or reset the computer, much to the chagrin of users who lost a day's work while erroneously trying to capitalize the letter Q. The 99/4's layout problems extended beyond the Q conundrum: The Enter key sat where a Right Shift key would normally reside on a standard layout. Also, the keyboard had a space key instead of a spacebar, and it was located in an odd position. The design had no dedicated Backspace key, either. At least TI learned from its mistakes and released the TI-99/4a, which came with a full-stroke keyboard.